Zhu Shanshan, Mi Junzhen, Zhao Baoping, Wang Zhaoming, Yang Zhixue, Wang Mengxin, Liu Jinghui
Coarse Cereals Industry Collaborative Innovation Center, Inner Mongolia Agricultural University, Hohhot, China.
National agricultural scientific research outstanding talents and their innovation team, Inner Mongolia grassland talents innovation team, Hohhot, China.
Front Plant Sci. 2024 Sep 19;15:1439747. doi: 10.3389/fpls.2024.1439747. eCollection 2024.
Drought stress inhibits oat growth and yield. The application of fulvic acid (FA) can improve the drought resistance of oats, but the corresponding molecular mechanism of FA-mediated drought resistance remains unclear. Here, we studied the effects of FA on the drought tolerance of oat leaves through physiological, transcriptomic, and metabolomics analyses, and identified FA-induced genes and metabolites related to drought tolerance. Physiological analysis showed that under drought stress, FA increased the relative water and chlorophyll contents of oat leaves, enhanced the activity of antioxidant enzymes (SOD, POD, PAL, CAT and 4CL), inhibited the accumulation of malondialdehyde (MDA), hydrogen peroxide (HO) and dehydroascorbic acid (DHA), reduced the degree of oxidative damage in oat leaves, improved the drought resistance of oats, and promoted the growth of oat plants. Transcriptome and metabolite analyses revealed 652 differentially expressed genes (DEGs) and 571 differentially expressed metabolites (DEMs) in FA-treated oat leaves under drought stress. These DEGs and DEMs are involved in a variety of biological processes, such as phenylspropanoid biosynthesis and glutathione metabolism pathways. Additionally, FA may be involved in regulating the role of DEGs and DEMs in phenylpropanoid biosynthesis and glutathione metabolism under drought stress. In conclusion, our results suggest that FA promotes oat growth under drought stress by attenuating membrane lipid peroxidation and regulating the antioxidant system, phenylpropanoid biosynthesis, and glutathione metabolism pathways in oat leaves. This study provides new insights into the complex mechanisms by which FA improves drought tolerance in crops.
干旱胁迫会抑制燕麦的生长和产量。施用黄腐酸（FA）可以提高燕麦的抗旱性，但FA介导的抗旱性相应分子机制仍不清楚。在此，我们通过生理、转录组和代谢组学分析研究了FA对燕麦叶片耐旱性的影响，并鉴定了FA诱导的与耐旱性相关的基因和代谢产物。生理分析表明，在干旱胁迫下，FA提高了燕麦叶片的相对含水量和叶绿素含量，增强了抗氧化酶（超氧化物歧化酶、过氧化物酶、苯丙氨酸解氨酶、过氧化氢酶和4-香豆酸辅酶A连接酶）的活性，抑制了丙二醛、过氧化氢和脱氢抗坏血酸的积累，降低了燕麦叶片的氧化损伤程度，提高了燕麦的抗旱性，并促进了燕麦植株的生长。转录组和代谢物分析揭示了干旱胁迫下FA处理的燕麦叶片中有652个差异表达基因（DEGs）和571个差异表达代谢物（DEMs）。这些DEGs和DEMs参与了多种生物过程，如苯丙烷类生物合成和谷胱甘肽代谢途径。此外，FA可能参与调节干旱胁迫下DEGs和DEMs在苯丙烷类生物合成和谷胱甘肽代谢中的作用。总之，我们的结果表明，FA通过减轻膜脂过氧化和调节燕麦叶片中的抗氧化系统、苯丙烷类生物合成和谷胱甘肽代谢途径，促进干旱胁迫下燕麦的生长。本研究为FA提高作物耐旱性的复杂机制提供了新的见解。
